Ignition distributors

ABSTRACT

A method of assembling an ignition distributor including the steps of engaging an annular timing plate with an annular base plate so that the timing plate is capable of angular movement with respect to the base plate. Three ears formed on the base plate overlie the timing plate, and the timing plate is rotated relative to the base plate, so that three ramps provided on the timing plate engage the ears respectively. As the timing plate is rotated the ramps bend the ears away from the timing plate, so that a clearance exists between the ears and the timing plate which is substantially equal to the heights of the highest part of the ramps above the surface of the timing plate. Thus the timing plate will be capable of a predetermined degree of axial movement relative to the base plate.

[4 1 Sept. 16, 1975 IGNITION DISTRIBUTORS William Harold Cooksey, Walsall. England [75] Inventor:

[73] Assignee: Joseph Lucas (Industries) Limited,

Birmingham. England [22] Filed: Aug. 12, 1970 [21] Appl. No.: 63,246

[30] Foreign Application Priority Data Dec. 24, 1969 United Kingdom 62777/69 [52] US. Cl. 29/598; 200/19 R [5|] Int. Cl. H02l 15/02 [58] Field of Search 29/437, 438, 598;

[56} References Cited UNITED STATES PATENTS 1.41 1.304 4/1922 Schneider et al. 200/19 R 1,908.274 5/1933 Walther 200/19 R Primary Examiner-Robert L. Spicer, Jr.

Attorney, Agent, or Firml-lolman & Stern 5 7 ABSTRACT A method of assembling an ignition distributor including the steps of engaging an annular timing plate with an annular base plate so that the timing plate is capable of angular movement with respect to the base plate. Three ears formed on the base plate overlie the timing plate, and the timing plate is rotated relative to the base plate, so that three ramps provided on the timing plate engage the ears respectively. As the timing plate is rotated the ramps bend the ears away from the timing plate, so that a clearance exists between the ears and the timing plate which is substantially equal to the heights of the highest part of the ramps above the surface of the timing plate. Thus the timing plate will be capable of a predetermined degree of axial movement relative to the base plate.

4 Claims, 3 Drawing Figures IGNITION DISTRIBUTORS This invention relates to a method of assembling ignition distributors of the kind including a base plate which is secured to the casing of the distributor, and a timing plate mounted for angular movement on the base plate, the timing plate carrying the contact breaker assembly of the distributor A method according to a first aspect the invention includes the steps of engaging an annular timing plate with an annular base plate so that mating surfaces on the two plates locate the timing plate for angular move ment on the base plate deforming three ears formed on a first plate of the pair of plates defined by the timing plate and the base plate towards the surface of the second plate remote from the first plate, said ears being disposed on the first plate in such a manner that any one of the ears is on the opposite side of a diameter of the first plate from the remaining ears. and moving the first plate angularly relative to the second plate so that three ramps upstanding from the second plate engage the ears respectively and deform the ears away from said surface of the second plate so that a predetermined clearance substantially equal to the heights of the highest parts of the ramps above said surface of the second plate, exists between the second plate and the ears thereby rendering the first and second plates capable of relative axial movement through said predeter-- mined distance,

A method according to a second aspect of the invention includes the steps of engaging an annular timing plate with an annular base plate so that mating surfaces on the two plates locate the timing plate for angular movement on the base plate and three cars formed on a first plate of the pair of plates defined by the base plate and the timing plate overlie the surface ofthc second plate remote from the first plate. the ears being disposed on the first plate in such a manner that anyone of the cars is on the opposite side of a diameter of the first plate from the remaining ears and moving the first platc angularly relziti c to the second plate so that three ramps upstanding from the second plate engage the ears rcspccti cly and deform the cars away from said surface of the second plate, so that a predetermined clearance substantially equal to the heights of the highest parts of the ramps above said surface of the second plate. exists between the second plate and the ears thereby rendering the first and second plates capable of rclati c avizil movement through said predetermined distance.

One example of the invention is illustrated in the accompanying drawings wherein Fl(i l is a diagramatic. fragmentary sectional view showing part of tlic distributor at one stage during its assembly FIG 2 is a cctional dizigr'aniutic representation of an assembled distributor. and

Referring to thc drn iing the distributor includes an annular lube ylhc i l l iU-lllL pan t n-metrically op positc tag lo t \howni by lilLJl'n of "vvhitli the basc PldlL' ll trin b luonrtcd v lllli'l tlrt using ol an ignition tlistrihLri-u lht will l lllL .czrlziil bolus of thc plntc li is t l\l1\lL"l ll right ,mglt lic lunc l the plan it to dc'im. i h rt im broil ug l. and up l'iltllfiL lion rht' -vrzphcr. f rho plutc ll inc thrcc t t'li lllltll i c Uni ll only or: l -lilLll is ho-u u, l he ears 12 are integral with the plate 11, and for conve nience are equiangularly spaced about the periphery of the plate 11. Each car 12 includes an arm 12a, which, prior to the assembly of the distributor. lies in the plane of the remainder of the car 12, that is to say at right angles to the plane of the plate 11. An annular timing plate 13 which will carry the contact breaker assembly of the distributor is engaged with the plate ll, the spigot of the plate ll entering the central hole in the plate 13 and serving to locate the plate 13 for angular movement relative to the plate ll about the axis of the spigot of the plate 11. A deforming tool is engaged with the arms 12a, of the ears [2, and the arms [2a, are bent to overlie the plate 13. The ears 12 are then deformed so that the arms 12a, engage the upper surface of the plate 13, whereupon the deforming tool is removed The plate 13 is provided with three upstanding ramps 14. The ramps 14 are upstanding from the upper sur' face of the plate 13, and for convenience are equiangularly spaced around the periphery of the plate 13. It will be appreciated that when the cars 12 are deformed so that their arms 12a. engage the upper surface of the plate 13, then the plate 13 is held against axial movement relative to the plate 11. However. it is required that there shall be a predetermined degree of permitted axial movement between the plate [3 and the plate 1 l, and in order to render the plates 13, ll capable of such relative axial movement the plate 13 is rotated relative to the plate I l about the axis of the spigot of the plate 1 l to cause the ramps 14 to engage the arms 12a of respective cars 12. When ramps l4 engage the arms 12:: the plate 13 is rotated further in the same direction relative to the plate ll to cause the ramps to ride under the arms lZu whereby deforming the ears l2 in a direction to move the arms 12a away from the upper surface of the plate 13. The heights of the ramps 14 are so chosen that when the ramps 14 have passed beneath the arms [20. then the distance between the upper surface of the plate 13 and the lower surface of the arms 12 is equal to the desired axial freedom between the plates I1 13.

In an alternative construction the base plate is formed with the arms [20 bent to lie parallel with the plate ll and spaced from the plate ll by a distance substantially equal to the thickness of the plate 13. The plate 13 is formed with slots 15 adjacent each of the ramps 14 and in order to assemble the plates, the spigot of the plate ll is engaged in the hole of the plate 13 and the plate 13 is aligned angularly with the plate ll so that the arms 12o pass through the slots [5. The plate 13 is then rotated relative to the plate II to cause the ramps [4 to engage and lift the arms 12a as described abo e Slots and ramps additional to those described above can be provided on the plate 13. so that common plates 13 can be used in distributors in which the plate 13 is required to mo c clockwise or anticlockwise. Thus \ihcrc the base plate 11 has three arms 12: then the plate [3 ould have two sets of three oppositely oricntcd ramps I4. and I441,

The assembly defined by the plate l l and the plate 13 is inserted into thc casing 21 of an ignition distributor and thc assembly is secured to the casing 2| by in etting scrc s through the holes in the tags on the plate ll. the screws engaging the casing of the distributor. lhc cam shaft 22 of the distributor ettcnds upwardly through the spigot of the plate ll. and the contact breaker assembly of the distributor is mounted on the upper surface of the plate [3. A vacuum advance capsule secured to the casing of the ignition distributor is connected to the plate 13 by means of a connecting rod, and the plate I3 is moved relative to the casing of the ignition distributor upon operation of the vacuum capsule the plate l3 moving about the axis of the spigot of the plate 11 to effect adjustments in the ignition timing of the distributor. The cam shaft of the distributor is coaxial with the spigot of the plate ll, and so movement of the timing plate l3 adjusts the ignition timing of the distributor without altering the operating gap of the contacts of the contact breaker assembly. The casing 21 is closed, in use. by an insulating cap 23. and the plate [3 carries nylon bearing pads which engage the plate ll and which reduce the friction between the plate 13 and the plate ll.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

l. A method of assembling an ignition distributor of the kind specified including the steps of: engaging an annular timing plate with an annular base plate so that mating surfaces on the two plates locate the timing plate for angular movement on the base plate; deform ing three ears provided on a first plate of the pair of plates constituted by the timing plate and the base plate. towards the surface of the second plate remote from the first plate, said ears being provided on the first plate in such a manner that any one of the ears is on the opposite side of a diameter of the first plate from the remaining ears; and moving the first plate angularly relative to the second plate so that three ramps upstanding from the seond plate engage the ears respectively and deform the ears away from said surface of the second plate. so that a predetermined clearance substantially equal to the heights of the highest parts of the ramps above said surface of the second plate, exists between the second plate, said predetermined clearance thereby rendering the first and second plates capable of relative axial movement through a predetermined distance.

2. A method of assembling an ignition distributor of the kind specified including the steps of: engaging an annular timing plate with an annular base plate so that mating surfaces on the two plates locate the timing plate for angular movement on the base plate, and three cars formed on a first plate of the pair of plates constituted by the base plate and the timing plate overlie the surface of the second plate remote from the first plate, the ears being disposed on the first plate in such a manner that anyone of the cars is on the-opposite side of a diameter of the first plate from the remaining ears; and moving the first plate angularly relative to the second plate so that three ramps upstanding from the Second plate engage the ears respectively and deform the ears away from said surface of the second plate. so that a predetermined clearance substantially equal to the heights of the highest parts of the ramps above said surface of the second plate. exists between the second plate, said predetermined clearance thereby rendering the first and second plates capable of relative axial movement through a predetermined distance.

3. A method as claimed in claim 1 wherein said step of engaging the timing plate with said base plate includes mounting said annular base plate for rotation upon a concentric cylindrical spigot formed in the base plate 4. A method as claimed'in claim 2 wherein said step of engaging the timing plate with said base plate includes mounting said annular base plate for rotation upon a concentric cylindrical spigot formed in the base plate. 

1. A method of assembling an ignition distributor of the kind specified including the steps of: engaging an annular timing plate with an annular base plate so that mating surfaces on the two plates locate the timing plate for angular movement on the base plate; deforming three ears provided on a first plate of the pair of plates constituted by the timing plate and the base plate, towards the surface of the second plate remote from the first plate, said ears being provided on the first plate in such a manner that any one of the ears is on the opposite side of a diameter of the first plate from the remaining ears; and moving the first plate angularly relative to the second plate so that three ramps upstanding from the seond plate engage the ears respectively and deform the ears away from said surface of the second plate, so that a predetermined clearance substantially equal to the heights of the highest parts of the ramps above said surface of the second plate, exists between the second plate, said predetermined clearance thereby rendering the first and second plates capable of relative axial movement through a predetermined distance.
 2. A method of assembling an ignition distributor of the kind specified including the steps of: engaging an annular timing plate with an annular base plate so that mating surfaces on the two plates locate the timing plate for angular movement on the base plate, and three ears formed on a first plate of the pair of plates constituted by the base plate and the timing plate overlie the surface of the second plate remote from the first plate, the ears being disposed on the first plate in such a manner that anyone of the ears is on the opposite side of a diameter of the first plate from the remaining ears; and moving the first plate angularly relative to the second plate so that three ramps upstanding from the second plate engage the ears respectively and deform the ears away from said surface of the second plate, so that a predetermined clearance substantially equal to the heights of the highest parts of the ramps above said surface of the second plate, exists between the second plate, said predetermined clearance thereby rendering the first and second plates capable of relative axial movement through a predetermined distance.
 3. A method as claimed in claim 1 wherein said step of engaging the timing plate with said base plate includes mounting said annular base plate for rotation upon a concentric cylindrical spigot formed in the base plate.
 4. A method as claimed in claim 2 wherein said step of engaging the timing plate with said base plate includes mounting said annular base plate for rotation upon a concentric cylindrical spigot formed in the base plate. 